This invention relates to gas-heat exchangers and particularly to gas-heat exchangers that may be used as lungs.
In one class of gas-heat exchanger, a perfusate is controlled in temperature by a heat exchanger and gas is introduced and removed from it through silicone rubber membranes.
In one type of prior art gas-heat exchanger of this class, the temperature of the perfusate is controlled by enclosing the entire perfusion instrument in a temperature-controlled environment. The perfusate passes through silicone rubber tubing that is randomly curved in a jar which contains oxygen.
This type of gas-heat exchanger has several disadvantages, such as: (1) enclosure of the entire perfusion system in a temperature-controlled environment made it difficult to carry out manipulations on the perfused organ; (2) inefficient removal of carbon dioxide due to a large gas compartment; (3) being large and difficult to handle because of the necessity of having a temperature-controlled environment; and (4) being subject to changes in carbon dioxide and oxygen exchange rates with time so that it is not repeatable.
In another type of prior art gas-heat exchanger of this class, the perfusate is passed through a heat exchanger and then through a tube which includes silicone rubber sacks enriched with oxygen. This prior art type of gas-heat exchanger has several disadvantages, such as: (1) being unreliable; (2) not repeatable in the exchange of carbon dioxide and oxygen; (3) being complex; (4) being expensive; (5) requiring separate heat exchangers and gas exchangers; and (6) generally not being reused.